Chinese Manufacturers Hydroxypropyl Methyl Cellulose/HPMC Production Method

Chinese Manufacturers Hydroxypropyl Methyl Cellulose/HPMC Production Method

The refined cotton cellulose was treated with lye at 35-40℃ for half an hour, pressed, the cellulose was crushed, and aged properly at 35℃, so that the average degree of polymerization of the alkali fiber obtained was within the required range. The alkali fibers were put into the etherification kettle, and epoxy propane and chloromethane were successively added for etherification for 5h at 50-80℃, with the maximum pressure of about 1.8mpa. Then add appropriate amount of hydrochloric acid and oxalic acid in 90℃ hot water washing material, make the volume expanded. Dehydrate in a centrifuge. Wash to neutral, when the water content in the material is less than 60%, dry with hot air flow at 130℃ to contain less than 5%. Finally crush through 20 mesh sieve to get the finished product.